1. Field of the Invention
This invention relates to light duty liquid detergents having particular utility in the hand washing of dishware, including dishes, pots, pans, glassware and silverware/flatware. More particularly, it relates to a liquid dishwashing detergent composition which provides stable, persistent foaming characteristics combined with good rinseability, mildness to the skin and effectiveness in removing greasy soils from dishware.
2. Discussion of the Art and Problems Solved
Foam generation by detergent compositions is associated by the consumer with good detersive ability. However, it is apparent that long lasting foam, whether considered copious or medium to medium-low foam content is, by itself, not a sufficient measure of cleaning ability. Nevertheless, much effort has been extended to optimize foaming characteristics, without necessarily improving cleaning ability.
Greasy soils are generally considered to be one of the most difficult soil types to be removed by hand washing. Effective grease removal is nearly always associated with requiring high temperature water to help dissolve and remove the grease.
Clearly, there would be a great advantage to formulate a mild, foaming, liquid hand dishwashing composition, which is capable of and effective in removing greasy soils as well as other soil types from dishware using water at ambient or warm to high temperature.
It has been known that among the anionic surfactants, those based on magnesium as the counterion (i.e. cation) can improve grease cutting performance. However, grease cutting performance is generally associated with increased irritation to the skin, e.g. hands, of the consumer.
It has also been known to use generally milder types of surfactants to ameliorate the somewhat harsh effects of the magnesium based anionic surfactants. Alkyl polyglucoside (APG) nonionic surfactants have been suggested for this purpose. However, although providing some foaming characteristics, the APG type surfactant has generally poorer foaming performance than other conventional foaming surfactants.
Another important characteristic to the consumer for hand dishwashing formulations is the ability to easily wash away the copious foam which is associated with good cleaning performance. Surfactant systems providing APG generated foams are not always acceptable in terms of rinseability.
Accordingly, it is an object of this invention to provide hand dishwashing aqueous compositions which combine acceptable mildness, foaming and grease cleaning performance.
It is another object of the invention to provide such compositions with good foam rinseability.
The present invention provides compositions which avoid the elevated problems and accomplish the foregoing objectives. The compositions, although prepared from otherwise known ingredients, but in unique combinations and proportions, is capable of achieving a new and beneficial result.